Digital BW, The Print

--- In DigitalBlackandWhiteThePrint@yahoogroups.com, "john dean" 
<deanwork2003@y...> wrote:
> 
> -Well that is very interesting indeed, that Photo Rag
> could absorb acid in such a quick and 
> devistating way. 

But we don't even know if it's "acid" (which begs the question of 
what acid it was and how the acid actually got from the newspaper to 
the prints).  An acid is a substance that produces excess H+ ions 
when dissolved in water.  The standard methods for measuring the 
acidity of paper (wet-end extract and cold water extract) depend on 
this.  If the newspaper and print are both dry then the actual 
transport mechanism of excess H+ ions from newspaper to print is a 
metter of pure speculation.

It's also pure speculation WHAT causes the discoloration.   At least 
with conventional photo prints, the chemistry is nonproprietary and 
it's well understood, so we KNOW what the factors are that can cause 
yellowing or color shifts.

With inkjet prints it could be ANYTHING.  Maybe your inkjet prints 
will be fine unless they just happen to be exposed to dog-breath 
while hanging near a Pothos plant.   I'll bet Wilhelm never checked 
for that!   "But, Peter", I hear people saying, "the inkjet prints on 
your cube wall, taped directly under a Pothos vine, without any glass 
or anything, look great after two years!   Doesn't that blow your 
whole theory?"    No, I say.  That's probably why the company doesn't 
allow dogs in the R&D facilities.

Seriously, it could be ANYTHING.   I live 3/4 mile from Rt 495 in 
Massachusetts.   How about NOx emissions?   I'm a painter, so how 
about turpenoid or mineral spirit fumes?   I clean my brushes with a 
powerful surfactants using either alkyl polyglycosides or ethylene 
glycol monobutyl ether or nonylphenol ethoxylates.  These irritate 
mucous membranes from several feet away - what will they do to inkjet 
prints?   We have a cleaning company come to clean our house every 
week - who knows what chemicals are in their cleaners?  

The list is endless and there is nobody on any of these photography 
and printing forums with enough chemistry background or a detailed 
enough understanding of the chemistry of the paper or inks to 
speculate intelligently about the problem.   We're all just a bunch 
ogf guys who don't actually know $#!+ about any of this, but thanks 
to what the Car Talk Guys call "male answer syndrome" we all feel 
like we have a right to BS about it.